The unions that represent various law enforcement agencies in New York City will join the fight to stop a federal monitor from overseeing the NYPD.

The unions, including the Patrolmen’s Benevolent Association, announced Wednesday night that they will file a motion to intervene in the landmark case where a judge decided to appoint the monitor.

If the motion is granted, the agencies can play an active role in the process to appeal the decision in the stop-and-frisk case.

“It is our collective view that this ruling may adversely impact the interest of the members that we represent,” said PBA president Patrick Lynch. “Police officers, detectives, lieutenants and captains are the boots on the ground in the fight against crime and terrorism.”

Law enforcement officials, including Police Commissioner Ray Kelly, have argued that the federal monitor will impede the work of officers.